1. Field of the Invention
The present invention relates to a portable terminal, and more particular to, a portable terminal having a transmitter for providing an audio input function for voice communication, etc.
2. Description of the Related Art
Generally, a portable terminal enables a user on the move to perform voice communication, message transmission/reception, schedule management, and reproduction of music files or moving pictures. With the development of electronic and communication technologies, the portable terminals have been miniaturized and have been equipped with other functions such as Internet or mobile banking services.
Meanwhile, to provide a voice communication function or a recording function, a portable terminal includes a transmitter equipped with a microphone for which a coin type microphone having a thin thickness smaller than a width thereof is often used.
FIG. 1 is a structural diagram of a known transmitter 10 of a portable terminal. As shown in FIG. 1, the transmitter 10 according to includes a microphone hole 13 formed to perforate from an outer wall into an inner wall of a housing 11. Inside the housing 11, a microphone 17 is mounted in a position corresponding to the microphone hole 13. The microphone 17 is installed inside a microphone holder 15 which is fixed inside the housing 11.
As shown in FIG. 1, the microphone 17 is an icon-type microphone and is disposed long in a longitudinal direction of the housing 11, taking account of a thickness of the portable terminal 10. In other words, the microphone hole 13 is disposed to face a front surface of the housing 11 and a sound input direction in which user's voice or the like is input is oriented in a sound input direction I of the microphone 17. Such disposition makes it easy to mount the microphone 17 in a slim portable terminal because the thickness of the microphone 17 is smaller than the width thereof.
Recently, with the common use of a portable terminal having mounted a touch screen therein, a microphone hole of a transmitter is usually disposed at a side of a housing of the terminal to improve the exterior design, more specifically, on a lower end portion of the housing. In this case, it is desirable to orient the sound input direction of a microphone toward the lower end portion of the housing, increasing the thickness of the terminal. Thus, the microphone is installed in the longitudinal direction, and a duct is formed from the microphone hole formed in the lower end portion of the housing up to the sound input position of the microphone.
FIGS. 2 through 4 show a conventional portable terminal in which a microphone is disposed long in the longitudinal direction of a housing where a duct is formed to connect the microphone with a microphone hole formed in the housing. The sound input direction I of a microphone 27 is oriented toward a front side or a rear side of a housing 21, but sound, such as user's voice, is substantially input in a longitudinal direction of the housing 21 from a lower end portion of the housing 21. When the voice sound arrives in the front side of the microphone 27, it travels in the same direction as the sound input direction I of the microphone 27.
The microphone 27 is disposed in the housing 21 while being enclosed by a microphone holder 25 made of an elastic material. The microphone holder 25 is fixed by a structure, such as a fixing rib, formed on the housing 21. In the microphone holder 25 is formed a duct 29 for connecting the microphone holder 23 with a sound input portion of the microphone 27. The duct 29 forms a portion of the microphone holder 25, such that the duct 29 is enclosed by the material forming of the microphone holder 25.
However, such a conventional transmitter structure has to entirely enclose the duct 29 with the same material as the microphone holder 25 which is a drawback in efforts to reduce the thickness of the transmitter structure. In other words, in a lower end portion of the microphone holder 25 shown in FIG. 3, the lower end portion of the microphone holder 25 enclosing the duct 29 needs to have a larger thickness to maintain the shape of the duct 29. Moreover, to smoothly deliver user's voice to the microphone 27, the duct 29 has to have a predetermined size. Therefore, there is a limitation in reduction of the thickness of the microphone holder 25 due to above requirements, thus hindering design efforts in miniaturization and slimness of the terminal.